- /// modified (i.e. a character is changed, a text is inserted,
- /// some part is deleted). This propery is also deleted if a
- /// property of the same key is added, which means that this
- /// property is not stackable. If this property is also
- /// FrontSticky (or RearSticky), text insertion just before (or
- /// after) the span also deletes this property from the span of
- /// text.
- Sensitive = 4,
+ /// modified (i.e. one of a character is changed, a text is
+ /// inserted, some part is deleted). Here, "span" means a
+ /// sequence of characters that has this property with the same
+ /// value. This property is also deleted if a property of the
+ /// same key is added, which means that this property is not
+ /// stackable. In addition this property is never merged with
+ /// the same value of preceding or following property. At last,
+ /// this property can't be sticky in any way.
+ Sensitive = 0x10, // 00010000
+
+ /// Like Sensitive but also this property is deleted from a span
+ /// of text if a characeter just before the span is modified,
+ /// inserted, or deleted.
+ FrontSensitive = 0x30, // 00110000
+
+ /// Like Sensitive but also this property is deleted from a span
+ /// of text if a character just after the span is modified,
+ /// inserted, or deleted.
+ RearSensitive = 0x50, // 01010000
+
+ /// Same as (FrontSensitive | RearSensitive).
+ BothSensitive = 0x70, // 01110000